Would it be feasible to convert a double rifle (such as the one in the link below) from 458 Winchester to 458 Lott?

Apologies if this is a stupid question, but my gun smithing tools consist of a checkbook and duct tape.

http://www.gunsinternational.c...cfm?gun_id=100175496

Before anyone answers, it occurs to me that regulation could be shot to hell by such a change.

I'm starting to think this was a dumb question.

I think it is a great question and there are people like J.J. Perodeau who can re-regulate it for a reasonable cost.

I'm interested in what the knowledgable folk here have to say to your first post ...

Maybe a conversion from 458 win mag to 450 3 1/4 would make more sense. I know that didn't answer your question but i believe it would be a better choice.

Will,

From a few minutes research, it appears to me that the best conversion would be to a 450 No. 2 NE 3.5". That case would completely cover the .458winmag in all places.

It is also a lower pressured cartridge which would make for less recoil. What a classy caliber in a Heym.

I believe the .458winmag is probably regulated with 500gr bullets, and the .450 No2 usually used 480gr bullets. But you could use either one based upon what the gun was originally regulated with. And you might just get lucky and not have to re-regulate it.

And if you do have to re-regulate, JJ can do it for a reasonable rate.

It might be worth it if you can get a real bargain on the Heym. I'm not sure what would need to be changed regarding the ejectors, if anything. Others here will probably know.

Mike

This was posted on the AFRICN HUNTING forum on the same rifle being questioned here!

quote:

Originally posted by Marty:
Nice rifle. My understanding is that extraction/ejection is more difficult to accomplish in this action type with a rimless cartridge. Ever see a rimless shotgun shell?

quote:

by MacD37:
OR.........Ever see a shotgun shell that produced 60,000 PSI chamber pressure?

quote:

By Marty:
That being said, I would think Heym has likely overcome the technical hurdle, but most double users would likely prefer rimmed cartridge. I think more of these guns were being made when traditional cartridges were harder to come by.

quote:

by MacD37:

The drawbacks in relation to rimless, high pressure cartridges in a break top double rifle are not fixed be fine fitting! I would trust the Heym far more than many other doubles with the 458 Win Mag chambering, but I would trust any good double rifle chambered for a flanged cartridge far more than even the Heym chambered for a belted rimless 458 win mag cartride!

The key with this rifle is to have JJ re-chamber the rifle to 450NE 3 1/4", an make a pair of solid ejector shoes, problem solved!

.458 Win Mag is a good cartridge and always will be. No need to change. PM AR member JPK...he has shot quite a few ele with his .458 WM double.

Will,

I am squarely in the group of rechamber to 450 NE.

Same ballistics. Classic rimmed cartridge.

Champlin's charges less than I would have suspected.

http://www.champlinarms.com/Default.aspx?tabid=28

From Champlin's site:

In the 60's a fairly large number of double rifles had been built in 458 Winchester mainly because of the disapperance of Kynoch ammunition. Today the 450 3 1/4 and 450#2 are available. Why keep a high pressure rimless round, when the nitro express calibers will achieve at least the same ballistics with the positive extraction of a rimmed case?

quote:

Originally posted by ledvm:
.458 Win Mag is a good cartridge and always will be. No need to change. PM AR member JPK...he has shot quite a few ele with his .458 WM double.

Lane there are many who have used doubles chambered for rimless/belted rimless high pressure cartridges without mishap! That fact doesn't change the fact that these things have some serious flaws in design when used in double rifles. One is on the re-load these things cannot just be dropped into the chambers simultaneously but must be pushed into the chambers one at a time! That is too slow! The biggest problem, however, is the tiny pawls that remove the empties from the chambers, in combination with the very high chamber pressure of most belted rimless cartridges.

The quick re-loading of the chambers is critical and simultaneous chamber charging is a must. The rimless/belted cartridge negates this!

If rimless/belted cartridges are not pushed past the pawls, and the rifle is slammed shut, the pawls can be broken off. There are two things that can occur when this is done!

#1 is that chamber will not extract and/or eject the empty from that chamber, and #2 the broken pawl may be caught between the extractor, and the back of the barrel and not allow the rifle to be closed fully, or jam the rifle closed!

JPK went through this discussion when he bought his rifle and decided to try it as is to see if it gave a problem. So far it hasn’t given him a problem! That is his good luck, but that rifle could have shown it’s little design draw-backs on the first elephant he went up against, and IMO, sooner or later it will rear it’s ugly head, and when it happens, my prediction is, it will be at the most inopportune time! Mr. Murphy would have it no other way!

............................

Hi Mac,

I defer to you on the rimmed vs. rimless in a double. You know a million times more than I on that subject. You have been one of my teachers over the years...you have never steered me wrong...the reason I bought a .500 NE!

My comment was more aimed at the fact that lengthening the chamber to a Lott was not going to be that helpful.

I'd be against this change. The only thing you gain is some velocity at the expense of higher pressures. IMO, a break action double is already pushed pretty hard with a 458WM, let alone the Lott. Even if it holds together, or even (doubtful) stays on face, think of the extraction. I believe this is already compromised by the rimless design of the cartridge.
What do you have against converting to 450 NE 3 1/4?
You don't need the velocity, it won't help penetration, which is the name of the game in a DGR. If you are worried the 450 won't do it (much the same as the 470) you need a 500 NE.
Remember, the 470NE was only developed after 45 cal. bullets were banned from the Empire, as this was considered a "military" caliber.

Go with a rimmed cartridge for positive extraction and much more acceptable pressures. The 450 straight or the 450 #2 would be great.

quote:

Originally posted by Marty:
I'd be against this change. The only thing you gain is some velocity at the expense of higher pressures. IMO, a break action double is already pushed pretty hard with a 458WM, let alone the Lott. Even if it holds together, or even (doubtful) stays on face, think of the extraction. I believe this is already compromised by the rimless design of the cartridge.
What do you have against converting to 450 NE 3 1/4?
You don't need the velocity, it won't help penetration, which is the name of the game in a DGR. If you are worried the 450 won't do it (much the same as the 470) you need a 500 NE.
Remember, the 470NE was only developed after 45 cal. bullets were banned from the Empire, as this was considered a "military" caliber.

I agree with most of what you say above, however, the LOTT produces no more chamber pressure that the 458 Win Mag! At the same bullet speeds it produces less pressure from the larger capacity case! A proper load for a double rifle re-chambered from 458 Win Mag to 458LOTT is to use a 480, or 500 gr bullet pushed at the velocities of the .450NE 3 1/4" cartridge! This will shoot exactly like the 458 Win Mag, but will produce much less chamber pressure!! Still I would go with the 450NE 3/14", or as will says the 450#2NE. The only draw-back to the #2 is it thins the chamber walls with the 500NE basic case,more than the 450NE, and the 450NE will clean the chamber of the 458 Win Mag as well, but doesn't thin the chamber walls as much as the 450#2NE.

Secondly the 470NE did not come about because of the .450 caliber ban in India, and the Sudan to keep the locals from using the bullets pulled from Military ammo in their muzzleloaders. That happened in late 1907, and the 470NE was introduced by Lang, around 1905, and released it to the trade in 1906! The reason the 470NE was so popular is the Lang allowed the cartridge to be used by the trade, rather than making it a proprietary cartridge. Be cause any maker could chamber their rifles to the 470NE it became very popular!

In the final analysis none of the .450/470 class of rounds is actually any better than the others, and is simply a toss up, and personal choice! The Cape buffalo doesn't care one way or the other! However, he also doesn't care if your rifle goes tits up when he is coming to administer an ass kicking either!

.................................. ...............

Thanks, Mac for the 470 history lesson. I had been misinformed. I really thought it was the 45 cal ban that prompted development.
I had not considered loading the Lott to Win Mag velocities. That makes perfect sense, and if I someday buy a 458 bolt gun, that's a great idea to lower pressures and ease extraction. It will be chambered for the Lott!

IMO, the Lott is a lot more recoil and not much greater effect on game then the 458 WM. Not to discourage play time, but it would be a waste of time and money.

As I discussed in my ele book, the 470 is everything the Lott is. Sell the 458 DR or re-do it to 450 NE or 450 No. 2 NE if you want a rimmed case.

One can load the 458 WM to insane velocities if wanted, with an associated increase in pressure. But the 458 WM plugging along at 2150 ft/s is quite do-able without any (imaginary) pressure or extraction problems.

The only advantage I see in rechambering to Lott is that you could use 550 grain bullets at 2,150 fps. The rifle will probably need to be reregulated for that load.

465H&H

Robgunbuilder did the WM-Lott conversion on a CZ O/U. You could ask him about it -- he liked it.

Personally, I like the .458 WM. Never tried it in a double though.

Although I have a DR that was originally a 458 win mag and is now a 458 lott I would not buy the rifle in question and re-chamber it,simply put the price does not justify it,it is not a bargain e.t.c
the regulation in my rifle never changed and it shoots just fine,I like it for what it is,it is a very accurate rifle,but I did not pay the price of a heym for it,I would pay 13,500 for a a rifle that needs no modifications.

Before embarking on this voyage I would read Hunting the African Elephant by Richard Harlan. He only shot over a thousand Elephants mostly with the 458 and the old supposedly dodgy ammo.

Yup I converted a CZ459 originally in .458 wm to a .458 Lott. It was easily done. just popped out the extractors and hand reamed with some dyechem on the belt recess. Regulation didn't change and the recoil increase to me was only marginally more. This gun shoots consistent 2 inch groups offhand at 50 yards. Extraction is extremely positive and I've never had an issue with it. Absolutely perfect in fact. Killed a pig two years ago on a Hunt in Texas with one shot at 125 yards. Put in a second one that hit 1/2 inch away. Only problem with this gun is everyone who sees it tries to buy it from me.-Rob

I've got a 458 Ruger #1 that was a 458WM and is now rechambered to a 450 NE. It cleans up the old chamber just fine.

But in a double it may require a re-regulation but you won't know til it's done. It migh be just fine as is.

quote:

Originally posted by Heym 450/400:
Maybe a conversion from 458 win mag to 450 3 1/4 would make more sense. I know that didn't answer your question but i believe it would be a better choice.

+1,2 or 3

SHUT UP AND SHOOT!!!

(That .458 is just fine like it is)

JW

quote:

by MacD37:

The key with this rifle is to have JJ re-chamber the rifle to 450NE 3 1/4", an make a pair of solid ejector shoes, problem solved!

+1

I believe that is the cheapest best way to go about it.
Since both shoot the 500 grain bullets in the vicinity of 2100 - 2150 ft/se I don't think there will be a regulation problem.

If you decide to go ahead and do the work, I would suggest that you shoot it with the 458 ammo first before going ahead with the conversion, so you will determine first if the rifle shoots well and second if it did change after the conversion.

Malek
Good shooting /hunting and God’s best

TOO MUCH PRESSURE, TOO SMALL OF AN EXTRACTOR to be SAFE in DR for DG!!

Go for a 450 NO.2 it will do the trick on all counts!...but 450 31/4" is available from Hornady...Ask JJ at Champlin, he has done it!

quote:

Originally posted by Jeff Wemmer:

(That .458 is just fine like it is)

JW

My thoughts exactly...leave it be. If it bothers you that much, find another one in Lott or 470 or whatever, and leave this one for someone that will appreciate it as it is.